Mower for tractors



Aug. l, 1944. u l|-1.w.s1Mx= sc N Erm.

MOWER FOR TRACTORS Filed June 9, 1941 4 sheets-snaai A1.

Aug. 1,1944. H. w. sxMPsoN ErAL.

MOWER FOR TRACTORS 4 Sheets-Sheet 2 www Filed June 9, 1941 ugl 1944 H. w. SIMPSON ET A1. 2,354,710

` MowER FOR TRACTORS Filed June 9, 1941 4 Sheets-Sheet 3 lNvEmoRs. #0h/5W@ hf. fnv/@JOM rrfq Mrz Patented Aug. 1, 1944 MOWER FOR TBACTORS Howard W. Simpson and Aram Abgarlan, De-

troit,'-Mich., assignors to Detroit Harvester Company, Detroit, Mich., a corporation of Michigan Application June 9, 1941, Serial No. 397,200

19 Claims.

This, invention relates to a mower for a tractor and ymore particularly to a rear mounte mower for a tractor.

In a mower for a tractor the sickle weighs several pounds and kmakes about nine hundred reciprocations or eighteen hundred strokes per minute. The reciprocation of .a heavy sickle at such high speeds sets up considerable and severe vibration which is very objectionable. At high sickle speeds the vibration is such that the tractor is subjected to a severe shaking which loosens the parts of the tractor and makes it uncomfortable for the driver. This vibration expresses itself mostly laterally or crosswise ofthe tractor. The vibration can be cut down by reducing the speed of the sickle. However, the slower the speed at which the sickle is operated the slower the speed at which the tractor can be run andthe less acreage that can be cut in any given-period of time.- If one desires to operate the tractor at a speed of six to eight miles per hour, then the sickle must operate at over `nine hundred reciprocations per minute.

It is an object of this invention to produce a light weight, high speed vmower for a. tractor which operates smoothly andA practically free from vibration. This object is achieved by a novel rubber mounting for the sickle drive which damps or dissipates the vibration set up by the sickle and thereby allows the sickle to be operated at a higher speed without harmful effects.l

This invention also contemplates a rear mounted mower for a tractorwhich can be quickly attached and detached.

This invention also contemplates a mower for a. tractor in which the drive mechanism will have a longer life compared with the driving units heretofore used. This object is achieved by sealing the drive within a housing and running the same in oil where ltcannot be reached by the dirt and dust incurred in the ordinary operation of a mower., v

Another feature of theinvention is an overload clutch incorporated in the drive mechanism and also mounted within the sealed housing. 'I'his overload clutch lets the sickle stop instantly whenever it cuts into lan obstruction.

This inventionA also contemplates a drive `mecl'lanis'm which 'can be quickly connected to the' power shaft of the tractor.

This object is achieved by means of a Vtelescopic drive shaft which can be readily slipped over the power take-off shaft of the tractorand drive shaft of the mower drive.

y In the drawings:

l ment arms 6 which are secured atftheir forward f Fig. 1 is a side elevation partly in section of the mower attached to the tractor. i 1 Fig. 21s a detail section along the line 2-2 of Fig. 4.

Fig. 3 is a fragmentary top plan view of ther mower attached to the tractor. l Fig. 4 is a'rearvview'of the mower and tractor. Fig. 5 is a vertical longitudinal section through the mower drive mechanism, telescopic drive shaft and spower take-off shaft of the tractor.

Fig. 6 is a section along the line 8--8 of Fig. 5. Fig. 7 is a detail'showing the attaching 'links` for connecting the mower to the tractor.

Fig. 8 is a section along the line 8--8 of Fig. 5. Referring more particularly to the drawings there is shown a portion of a tractor comprising the rear wheel I, `tire 2 mounted on the rear wheel, the driving axle 3, the axle housing 4,`the differential and power take-'0E housing 5.

The tractor comesrequipped with twov impleends by means of studs to the underside ofthe axle housing.' As a support for the driving mechanism of the mower there is provided a.

crossgbar 1 to which is affixed at each end the brackets 8. The rear vends of the implement bars 'I'he drive mechanism for the mower comprises i a housing I5 made in two sections which are secured together in sealed relation by lbolts I8. 'Ihe housing- I5 is provided with a hub 28 which is fixed `on to a stub shaft I 'l by set screw I 50. 'I'he stub shaftI'I is supported at oneiend by means of a soft rubber bushing or cylindrical sleeve 2| within a hollow housing I8 secured by boltsl! to the cross bar 1. 'I'he hub'2Il is also supported within the housing I8 by means of a soft rubber bushing or sleeve 22. Shaft I1 is retained in the housing I8 by end plate 23 and screw 24. The bushings 2| land 22 are made from soft rubber and are placed under relatively yhigh compression betweenshaft' I'l and housing I8. The bushings 2l and 22 are placed under compression by turning in screw 24. Screw 24 as it is turned in acts through plate 23 to place the bushings in compression. Bushing 2I alsoextends between end plate 23 and housing I8.

` Aa sprocket z5 having angustia rptatsblyfsup.,

sprockets and 30.

Sprocket 39 does not drive shaft 21 direct but The seal 39 is I9 is provided with a sleeve portion 82 which is swiveled upon the outer end of the drag bar 4I and retained thereon by nut 93. The other end of the drag bar 6I has a ball and socket connection 94 with the lower end of the housing I5. It will be noted that the ball and socket connection 84 is positioned very close to the point of connection between the pitman and flywheel 29. This drives the same through a ratchet type clutch.

The ratchet clutch comprises a sleeve 32 which is splined on shaft 21 so that it must rotate .with

shaft 21 but can slide longitudinally thereof.

V the axle housing 4 in bracket 12. Bracket 12 is The sleeve 32 is backed up'by al compression l spring 33 held in position by a washer 34 and nut Il.I The sprocket vand sleeve 32 are'provided with inter-engaging ratchet teeth 39. The comy,

preghlon of spring 33. can be adjusted by removing-.cap 31 and turning adjusting nut 35 which increases or decreases the load on ratchet teeth It vandV determines'the load at which the ratchet f Aclutch will'slip. The housing I5 is filled withoil so that the drive mechanism runs in `oil and is always assured of VNproper lubrication.

Sprocket 2i is driven from the powerl take-off shaft 33 with which the tractor is provided.'Y 'I'he driving connection between shaft 3l and sprocket `2I vcomprises a telescopicv driving shaft made v from a pair4 olf-.non-circular orsquare tubes 39 and 49, the latter of which is telescoped within the former. Aoompression spring. 4i is housed within the'tubes V4 9 and 39'and tends to separate the same. The telescopic drive shaft hascylindrical cup members 42 and 43 affixed at lopposite ends. A coupling sleeve 44 having internalV splines is secured within cup member 43 by means f and cup member 4I. Sleeve 44 is slipped overthe `the shaft Il. Asleeve 4l having a key 41 is mounted within cup'42 by a rubber bushing 43 alsoundercompression. yKey 41 has a sliding flt in keyway 4l formedin hub 2l. y

The telescopic drive shaft permits quick aslembly to themower by simply sliding the shaft 49 withinshaft "and-then vslipping sleeve 44 over the powertakeoif shaft` 33 and theV other end of the vshaft over `hub 2l. Spring 4| keeps the telescopic shaft expanded and inV driving relation with the power take-oi! shaft andthe hub 2t'. v n

The mower comprises the conventional mower bar 49 fixed at the inner end to the shoe III and ,a reciprocating sickle Il connected by a ball and socket joint l2 with one end of thel pitman I3. The other end of the pitman I3 is connected to the flywheel 29. This connection comprises a pin l4 (Fig. 5) fixed in opening` of the flywheel 29. A bearing knuckle Il, Figs. 3 and 4V, is jour'- nalled` on pin 54.l Bearing knuckle has a vertical pivotal connection with pitman i3 in the form of a pinll1 and yoke 58. Thus it'will be rseen that the connection vbetween the pitman 53- and the ywheel 29 is intheformof a universal joint.v j' j The sickle and mower bar are pivotalLv mounted on hinged bracket Il by means of pins W so that the mower bar and sickle can be swung up relation islmportant as explained below.

One end of pull rod 19 is welded or otherwise ilxed to the collar H9 as at 1I. The other end of the pull rod has a loose sliding fit in collar 13 integral with pin 14 which is journalled beneath supported on the housing 4. A compression spring 15 lspositioned over pull rod 1li between collar 13 and stop ring 19 on the end of the pull rod. Tlius, the rod 10 and collar 13 are free to swivel with pin 14 about a horizontal axis and the loose fit of rod 10 in collar 13 gives the rod somewhat of a universal joint connection with the collar 13 which is essential to avoid binding between the collar and pull Vrod whenever the mower bar and sickle breaks back. such as occurs when vanobstacle is hit.

Y The weight of the mower mechanism is counterbalanced by balance' spring 11. One end of spring 11 is connected as at^18 to bracket 19 above the axle housing 4. Bracket 19 is bolted to bracket 12. The other end kof `the balance spring 1'1 is fixed to rod 39 as at 8l. Rod 39 is swiveled to bell crank 92 as at 83.

Bell crank 32 is pivotally supported by means of pin I4 on hinged bracket B9. 'I'he axis about which bell crank l2 swings, that is, pin 94, extends upwardly andrearwardly, Fig. 1. One end of the'bell crank is connected by draft lnk85 with-lever supported on shaft l1. Shaft 91 I is connected toa hydraulic drive (not shown) within housing which serves'as a source of power for lifting the mower bar. The other end of the bell crank 92 is connected by means of link 99 with the upper end of a lever'90. 'The lower end ofthe lever 99 is pivotally connected to'shoe 59 by means of pin 9|. Lever 90 abuts against boss 92 of the shoe 59; Shoe 50,'as above explained, is pivotally mounted on bracket 59 by means of pins 40.

When it is desired to elevate the mower bar for any reason whatsoever, such as to clear a stump or in case one desires to run the tractor without having the mower in cutting position, the

hydraulic vlift mechanism is operated which swings lever 94 forwardly or clockwise, Fig. 1,

gr'ees acts through lift link v89 and lever 99 to swing the -mowerbar 49 upwardly about pivot pins 49 a few degrees. Upon further clockwise rotationv of the lever" and forward movement of lift link 'Il with bell crank 32 abutting stop Il, the mower bar 49 and shoe I9 are further elevated together because at this time drag bar 6I `swings upwardly about the ball and socket joint 94 and the pull bar 10 swivels upwardly on pin 14 until the shoe and mower bar are raised about a foot oi! the ground. If it is desired to raise the mower bar to vertical position, the same can be done at any time by'manually swinging the same a Aupwardly about pivot pins 99.

The tilt of shoe lll and mower bar can be to vertical or upright position. Hinged bracket adjusted by means of hand lever I 09. the lower end of which is ailxed to stop 95 on bracket 59. Swinging of lever causes the mower bar and shoe to tilt about drag bar 6|. The1ever|00 is held in adjusted position by means of pin |0| which passes through one of the adjustment openiings |02 in rod |03 pivoted to pull bar 10 at I0 In case the mower strikes a stump or other obstruction -the mower bar swings back against the compression of spring l15. During the break back, drag bar 6I swings about ball and socket joint il and pull rod slides in collar 13. l Whenever the break back of the mower bar occurs. rod |05 is drawn backwardly by bracket |06 a'lxed on pull bar 10. As rod |05 moves backwardly it operates through known mechanism, gener-v ally designated |5l, to disengage the. tractor clutch and apply the brake to the left hand wheel. f

In case the sickle and mower bar should run intoan obstruction, such as a large tree stump. the break back of the mower bar occurs and the sickle continues to reciprocate. However, in case the mower bar should run into an obstruction,

such as a steel stake or other object which can ber in compression. These rubber inserts 43 and Y I5 in the couplingshaft reduce the shock load on the moving parts of the mower and the wear and tear on the mowing machine by smoothing out load impulses. This gives greater life to the sickle sections and the ledger plates. These rubber inserts also allow for disalignment of the mower chain drive box relative to the tractor power take-off shaft due to any slight manufacturing variations.

The drive through the'sprockets 25 and 30 and chain 3l is transmitted through shaft 21 tothe pitman 53 which reciprocates the sickle at a very high speed. This sets up considerable vibration mostly crosswise or laterally of the tractor.

'I'hese vibrations are transmitted through the drag bar 5| and the pitman to the mower chain drive box or housing I5.. This causes the housing |5 to vibrate or swing about shaft `I1 supported in the rubber bushings 2|` and 22. These bushings 2| and 22 are in compression and during the vibration of the housing i5 are also in torsion when housing swings sideways of Athe tractor such as occurs when the mower is operating. These rubber bushings effectively damp and dissipate substantially all of the vibration set up by the sickle, pitman, and other moving parts `of the mower. Inasmuch as the entire chain drive housing I5 is hung in rubber to damp and practically eliminate the vibration inthe mower which would otherwise be transmitted to the tractor, the sickle can be operated at a much higher speed with the result that greater acreage can be mowed. With a mower having the above described rubber mounting, a sickle has been run at a speed as high as twenty-two hundred strokes per minute. At this sickle speed the mower cperates extremely'smoothly and the vibration is practically nil.

A further beneficial result of the rubber mounting of the housing I5 and of the rubber inserts in the telescopic drive shaft is that the whole mower can be made much lighter because of lower stresses.

The tractor even with thermower attached can be used for drawing other implements. These other drawn implements can be readily attached to the cross bar 1 in holes provided therefor for hauling .the same. obtained by having the driving mechanism of the mower all located ahead ofthe cross bar 1.

The telescopic drive shaft is important because it can be assembled after the rest of the mower has been completely mounted on the tractor. This facilitates the quick assembly of the mower to the tractor. that inthe break back of the mower bar the housing |5 and drive assembly, as welles the coupling Shaft, are not moved except for the side deflection ofv case |5 in the rubber. 'This is made possible by the fact that the vertical pivot of the pitman arm and the vertical pivot pin.51 and the ball and socket pivot 64 of the drag bar are lo cated close together. This permits both the pitman 53 and the drag bar 6| to swing backwardly on approximately the same radius without causing themv to'bind. This mounting ofthe vertical pivot 51 of thepitman arm and the ball and socket 64 ofthe drag bar 5| close together is also important because it -permits the mower bar and sickle to rise and fall as it passes over the ground while mowing without` causing the sickle to be displaced lengthwise appreciably in relation to the mower bar. In other words, each sickle section will always make a complete reciprocation from one ledger plate to the next which is highly desirable for efllcient cutting even though the mower bar and shoe 50 rises and falls with respect to the tractor.

The balance spring 11 reduces the wear of the shoe and mower bar against the ground and also prevents the mower bar from digging into the ground. This spring balance arrangement -gives a floating action which allows the mower bar tol ride lightly through the crop with a minimum of power. l

Referring to Fig. 3 it will be noted that the drag bar makes an angle of ninety degrees with the longitudinal center line of the tractor and that the pull bar 10 makes an angle of .about ninety degrees with the drag bar 6I.. `This feature is important because if the pull bar 10 .is positioned other than a right angle with drag bar 6| in the operation of the mower, the pull bar will tend to straighten out or swing into a position in which it is parallel to the longitudinal axis of the'tractor. In so doing, the mower bar 49 will swing backward about the drag bar and ball and socket joint. For eflicient cutting it is very desirable that the mower bar and sickle should be positioned perpendicularly to the direction Lof travel of the tractor, that is, the mower bar should make a right angle with the longitudinal axis of the tractor. This is achieved by arranging the pull bar 10 so that it makes a right angle with the drag bar 6I.

'I'he mower bar and shoe are pivoted tothe hinged bracket 50 about an axis which is inclined forwardly and upwardly. The axis 60-60 is tilted forwardly and upwardly to prevent the tendency for the shoe or inner end of the mower bar to raise, particularly under hardcutting conditions or when the outer end of the mower bar hits an obstacle'.

This feature of the mower is` It should also be noted As shown in Figs. 3 and `4, compression coil spring |52 is mounted 'over the drag, bar 8| between shoulder |53 integral with the drag bar It and'collar IIB. Hinged bracket 591s maintained onfdrag bar 6l by means of nut $3. Itv will besee'n that this mounting of the hinged bracket on the drag barprovides a very simple arrangement for adjusting the mower or ilnger Vbar with respect to the sickle to obtain proper -register of fthe sickle with the linger bar;

simply tightening or loosening nut 63 the nger bar and sickle can be:y brought into the proper register. Y

We claim: f f' l. In a mowing machine, the combination with an oscillating sickle and pitman for'oscillating the sickle, of driving mechanism for said pitman. a connection between said driving mechanism and said pitman, and a mounting for said driving mechanism of distortable elastic material in compressionand also in torsion when Vthe pity man is oscillating' for damping the vibration of the oscillating sickle and pitman. f v

2. Ina mowing machine, the combination with an oscillating sickle and pitman for oscillating the sickle, of a driving mechanism forsaid pitman, a connection between said driving mechanism and said pitman, a rigid xed support, and

a mounting of distortable elastic vmaterial in' compression and also in torsion when the sickle and pitman are oscillating for iloating the driving mechanismen the support wherebythe vlbration ofthe ioscillatingsickle and pitman is damped.

3. In a mowing machine, the combination with an oscillating sickle and pitman for'oscillating the sickle, of a'driving mechanism forfsaid pitman, a connection between said driving mechanism and said pitman, a support for said driving mechanism, a rigid ilxed support for said iirst mentioned support, and a pivotal mounting inthe vibration ofthe oscillating sickle and pitman are damped.

5. Ina mowing machine, the combination with an oscillating sickle and pitman, of a driving mechanism, a connection between said driving mechanism and said pitman, a support for said driving mechanism, a second support member, and a mounting including a shaft xed to one of said Y aforementioned members and distortable elastic material carried by the other member and supporting said shaft in said other member for yiloating the driving mechanismjsupport on the said second support, the said distortable elastic material being in compression at all times and also in torsion when the driving mechanism is run.- ning whereby the elastic support damps the vibration ci' the oscillating sickle and pitman.

6. In amowing machine, the combination with" an oscillating sickle and pitman, of ra' drving mechanism, a connection between said'driving mechanism and said pitman, a housing for said Byl man, a connection between said driving mechanism and said lpitman, a housing for said driving mechanism, a stub shaft for supporting said housing, and a distortable elastic support for said stub shaftythe said distortable elastic support being in compression and also in torsion when the sickle and pitman are oscillating.

8. In a mowing machine, the combination with an oscillating sickle and pitman for oscillating the sickle, of a driving mechanism for said pitman, a connection'between said driving mechanism and said pitman, a rigid support, a shaft supporting saidy driving mechanism, and rubber bushings in compression for mounting said shaft on 1 said rigid support whereby the bushing is also in torsionwhen the sickle and pitman are oscillating and functions to dampen the vibration of the oscillating sickle and pitman.

9. In a mowing machine, the combination with an oscillating sickle and pitman, of driving' Y support, a mowing machine including an oscillatupon the rigid support of the tractor, said elastic mounting being in compression and also in torsion when the oscillating sickle and pitman are oscillating whereby the vibration is damped.

1l. In combination with a tractor having a rigid support, a mowing machine including an oscillating sickle and pitman for oscillating the sickle, driving mechanism for said pitman, a

connection between said driving mechanism and said pitman, and a mounting of distortable elastic material for'supporting said driving mechanism upon the rigid support of the tractor, said elastic mounting being in compression and also in torsion when the oscillating part is oscillating whereby the vibration is damped, and a power take-off shaft for said tractor, and a shaft mounted in rubber for connecting the power takeoil.' shaft with said driving mechanism.

12; In combination with a tractor having a rigid support, a mowing machine including an oscillating part, driving mechanism for said part, and a mounting of distortable elastic material for suporting said driving mechanism upon the rigidsupport of the tractor, said elastic ,mountingfbe ing in compression and also lin torsion when the oscillating part is oscillating whereby the vibration is damped, said tractor having a power takeoil shaft, said driving lmechanism including a rotary member having a portion projecting without the housing, a telescopic drive shaft adapted to be slipped over the power take-oi! shaft and said other shaft for connecting the power take-off shaft with the driving mechanism for the mower.

13. In combination with a tractor having a rigid suport, a mowing. machine including an oscillating part, driving mechanism for said part, and a mounting of distortable elastic material for supporting said driving mechanism upon the rigid support of the tractor, said elastic mounting being in compression andalso in torsion whenithe oscillating part is oscillating whereby the vibration is damped, said tractor having a power takeo shaft, said driving mechanism including a rotary member having a portion -Projecting without the housing, a telescopic drive shaft adapted to be slipped over the power take-olf shaft and said other shaft for connecting the power takeof! shaft with the driving mechanism for the mower, and a rubber mounting for each end of the telescopic shaft whereby the same is floated in rubber and serves to smooth out loadimpulses.

14. In combination with y a tractor having a rigid support, a mowing machine including an a sickle, a mower bar for the sickle, a pitman,` and a driving mechanism for the pitman including a rotating ywheel, a support for the driving mechanism floated in distortable elastic material held in compression, and a drag bar pivotally connected at one end to the support vadjacent the' connection between the pitman and the pitman flywheel whereby the mower sickle and mower bar can be elevated without causing the sickle to become displaced lengthwise appreciably in sickle and Pitman. i v

oscillating sickle and pitman for oscillating the sickle, a driving mechanism for said pitman, a mountingl of distortable elastic material for mounting the driving mechanism on said rigid support, and a drag bar also having one end con- -nected to said rigid support by4 means of said housing on the support, a drag bar,.and a pivotal connection between one end -of the drag bar and the said housing whereby the distortable elastic a materialdampens the vibration set up inthe operation of the mower.

16. In a mowing machine, the combination of 18. In a mowing machine, the combination with y an oscillating sickle and pitman, of a driving mechanism, a housing for said driving mechanism, a flywheel mounted on said housing and connected to one end oi' the pitman, a support, a pivotal mounting for the housing on the said support, and resilient `elastic means acting between the housing and the said support for clampV ing the vibration created by the oscillating sickle.,

and pitman.

19. In a mowing machine, the combination with an osclllatingsickle and pitman for oscillat- ,ing the sickle, of s. driving mechanism for said swingably mounting said housing on rigid .support whereby the bushing is also 'in torsion when the sickle and pitman are oscillating and-v functions to dampen the 'vibration of the oscillat- HOWARD w. N. 

